Waste and Emission Reduction Alternatives for Dry CleanersPerchloroethylene (perc) is a commonly used solvent in the dry cleaning industry. It is released into the environment from clothes transfer, waste removal, and fugitive or uncontrolled emissions. Many opportunities exist to reduce perc use, including:• Improved operating and maintenance procedures• Moreefficientequipment• Incorporation of substitute cleaning products and methodsAnumberofbenefitscanbegainedbytakingstepstoreduceperc from dry cleaning operations. These include:• Saving money on perc purchase and disposal• Reducing employee exposure to perc• Providing greater environmental protection• Reducingregulatoryrequirements• Reducing liabilityPerc purchasing costs continue to rise. This is partly due to taxes and fees levied in several states to support perc cleanup funds. In addition, reducing perc use and its release to the environment helps meet many regulatory requirements.Theserequirementsinclude:• The Occupational Safety and Health Administration (OSHA) 25 parts

per million (ppm) limit during an eight hour period for employee exposure (100 ppm at the Federal level)

• The Clean Air Act National Emission Standards for Hazardous Air Pollutants (NESHAP) for perc dry cleaning facilities

• Hazardouswasterequirements

Operating and Maintenance PracticeThefirststepinusingproducts,orexistingequipment,moreefficientlyistogainanunderstandingoftheirusethroughemployeetrainingonequipmentoperationandmaintenance.Whetheradrycleanerhastransferordry-to-dryequipment,bothrunmoreefficientlywhenoperatedandmaintainedaccordingtomanufacturerspecifications.Therearefourcategoriesofoperatingandmaintenancepractices:1. The machine itself2. Auxiliaryequipment3. Control devices4. Generalhousekeeping

This publication is issued by the Oklahoma Department of Environmental Quality authorized by Scott A. Thompson, Executive Director. Copies have been prepared at a cost of $0.212 each. Copies have been deposited with the publications clearinghouse of the Oklahoma Department of Libraries. (Fact Sheets\AQD\Waste Alternatives for Dry Cleaners.indd 6/2019)

This waste and emission reduction guide for dry cleaners provides an overview of improved operating techniques,upgradedequipment,and substitute or alternative cleaning products to help cut costs by reducing perc use.

Waste and Emission Reduction Alternatives for Dry Cleaners

The following section of this guide provides general recommended operating and maintenance practices. Dry cleaners should alwaysconsultequipmentoperatingmanualsfrom manufacturers and service companies for specificrecommendationsonthemachineandcontrol device that they operate.

Machine MaintenanceRegular machine maintenance procedures involvecheckingforleaksarounddoorseatingsandgaskets,hoseconnections,pipefittings,exhaustdampers,ductwork,linttraplids,andwater separators. In addition, certain component parts should be cleaned regularly, including condensing coils, strainers and the lint bag.

Auxiliary EquipmentAuxiliaryequipmentincludesfilters,waterseparator,distillationunits,andmuckcookers.

• Regularlycleanandchangefilters.Cleantheperc/waterseparatortankandsteam/condensation coils (if necessary).

• Adjust perc/water separator correctly, and checkseals,gasketsandventsforleaks.

• Solvent containment troughs are a safety measure for new or existing machines. The machine sits in the trough which is designed to capture solvent that might be spilled while adding solvent, cleaning the still,orfromabrokenfittingorleakingtankon the machine.

Control DevicesControl devices may include external refrigerated condensers and carbon adsorbers.• Foreitherofthesedevices,lintfilters

should be cleaned daily, and lint should be removed monthly from refrigerated condenser coils.

• Checkforleaksregularlyaroundgaskets,seals,valvesandductwork.

• Carbon adsorbers should be desorbed daily and perc concentrations in exhaust air measuredweekly.

• Forunitsequippedwithrefrigeratedcondensers, temperature measurements

shouldberecordedweeklyatboththeinletand outlet to the condenser for transfer machines and at only the outlet for dry-to-dry machines.

• Logs to record perc concentration readings forunitsequippedwithcarbonadsorbersandtemperaturereadingsforunitsequippedwith refrigerated condensers are provided on our website.

General HousekeepingGeneralhousekeepingpracticesinclude:• keepinglidsonallcontainers,• properly labeling all perc and waste

containers,• keepingmachinedoorsandtrapsclosed,• sizing garment loads correctly,• using spigots, pumps and funnels when

transferring perc and waste materials.Manyofthesepracticesarealsorequiredunderthe perc dry cleaning NESHAP.

Equipment UpgradesThe price of perc continues to rise. Dry cleaners that use perc may want to consider upgrading tomoreefficientequipmenttoreducepercloss,which will in turn reduce the amount of perc that must be purchased.

Dry-to-Dry MachinesSwitching from traditional transfer machines to amoreefficientrefrigerateddry-to-drymachineeliminates garment transfer, and can reduce perc use and purchase in a given year by as much as 90 percent.• The newest dry-to-dry machines are

equippedwitharefrigeratedcondenser,whichisveryefficientatrecoveringpercandrecyclingitbackthroughthemachine.

• The new, tighter machine design also significantlyreducesfugitiveemissions.Perc recovery from waste is increased with thenewspin-filterdesignordiscfiltration,resulting in less waste generated, lower perc emissions from waste removal, reduced operator exposure to perc, and lower overall perc loss and cost for disposal.

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Waste and Emission Reduction Alternatives for Dry Cleaners

Emission-free still sludge is another feature of new machines that dramatically reduces perc in sludge and lowers operator exposure to perc fumes. With this system, the sludge is pumped from the still to a waste barrel with fumes ventedbackintothecleaningmachine.Finally,newmachinesareequippedwithapercdryingsensor which runs through a microprocessor and monitors perc concentrations in the clothes by sensing perc returning from the condenser during drying. When properly programmed, it prevents operators from short cycling loads with the inherent loss of perc to the atmosphere and exposure of operators to excess vapors.

Refrigerated CondensersIf purchasing a new refrigerated dry-to-dry machine is not cost effective for a dry cleaner, a refrigerated condenser could be added to a non-refrigerated, dry-to-dry or transfer machine. Furthermore,suchmodificationmaybenecessary to ensure compliance with the perc dry-cleaner NESHAP.

Carbon Adsorption UnitsCarbon adsorption units may be added to refrigerated dry-to-dry machines to achieve greater perc recovery. However, machines withrefrigeratedcondensersworksowellatrecovering perc that adding a carbon adsorber to a newer machine may not be cost effective. Additionally, traditional carbon adsorbers requireahighlevelofmaintenance,andthecarbon should be desorbed daily to ensure effective removal of perc from the vent stream.

Oncethecarbonadsorptionsitesarefilled,percisnotcapturedefficientlyiftheunitsarenot maintained. Also, over time, the carbon does not desorb as effectively and eventually it would need to be replaced in the unit. New carbon units that desorb with heat are not as costly to operate, and do not produce large quantitiesofcontactwaterfromsteamusage.

Alternative Cleaning SystemsIn any industrial application, minimizing solvent use is a desired goal to cut costs, reduce employee exposure, protect the environment and reduce the burden of environmental

regulations. Alternatives to solvent cleaning are rapidly gaining acceptance in many different types of cleaning applications.

Minimizing perc use in solvent cleaning of garments is also a desired goal for the above reasons. Some alternatives are gaining acceptanceslowly,suchasaqueouscleaning.Alternative garment-cleaning systems are generally used in combination with one another. They are not necessarily a total replacement of perc dry cleaning; but, by using them in combination,relianceonperccanbecutback,thereby minimizing perc use.

Many dry cleaning facilities are using petroleum-based cleaners, which are much less toxicthanperc,requiremuchlessmonitoring,and are cheaper to operate. Depending on the total dryer capacity of facilities using petroleum cleaners,therequirementsofNewSourcePerformance Standards (NSPS) Subpart JJJ may apply.

Aqueous CleaningAqueous,orwet,cleaningmayhavethepotential to replace perc cleaning for 30-100 percent of garments. This process uses water and detergents in temperature and agitation computer-controlled washing and drying machines.

These machines can accommodate most dry-clean-only garments because:

• They reduce agitation during washing• Increase extraction of water prior to drying• Usespecificallyformulatedwet-cleaning

soaps and spotting agents• Heat and moisture content are closely

monitored during the drying process.• Wet cleaning may be preceded by spotting,

steamingorhand-washingtechniques.The wet cleaning system may be operated in tandem with a perc cleaning unit to meet cleaning needs and to help operators gain confidenceinthewetsystem’scleaningabilities. A wide range of garments can be run in the wet-cleaning unit, including:

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Waste and Emission Reduction Alternatives for Dry Cleaners

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weddinggowns,woolsuits,silks,cottons,leather and bead-trimmed garments, comforters, and some rayon-acetates. Customers and shop owners report good cleaning, brightness and fresh-smelling clothes, with few customer complaints.

A number of shops are also opening up across the country as dedicated wet cleaning shops. Most dry cleaning industry analysts agree thatwetcleaningisakeypartofthefutureofprofessional garment cleaning.

Horizon TechnologiesEven more revolutionary cleaning systems are on the horizon, such as:

• dry wash, which is a carbon dioxide technology that does not use solvents and may be more effective than water-based technologies in the future, or

• ultrasonic cleaning, which is also being tested as an innovative cleaning method with many applications. Early testing on fabricswatcheshasshownthatadequatecleaning is achieved for most soils, without redeposits occurring.

Environmental CertificationDrycleanerswhowishtobecomeaCertifiedEnvironmental Dry Cleaner must pay a fee and passanexamination.Thecertificationcoversequipmentoperatingprocedures,environmentalregulations and proper waste handling, and is offered through the International Fabricare Institute. A self-study guide is available from the Professional Testing Corporation to prepare for the examination.

Sources For More InformationOklahoma Department of Environmental QualityPollution Prevention and Small Business Assistance,OfficeofExternalAffairsPhone: (405) 702-7197, (405) 702- 8179, or (800) 869-1400Website: www.deq.state.ok.us

Professional Testing CorporationPhone: (212) 356-0660Drycleanerenvironmentalcertificationhandbook

Drycleaning & Laundry Institute14700 Sweitzer LaneLaurel, MD 20707Phone: 301-622-1900 (or) 800-638-2627Fax: 240-295-4200Website: www.dlionline.orgE-mail Address: techline@dlionline.orgInternational membership and program informationCertificationandtraining